Novel approach to mars orbiter mission software quality assurance

Mars Orbiter Mission (MOM) of Indian Space Research Organization (ISRO), being a deep space interplanetary mission, has to face several challenges due to the constraints like increase in round trip communication delay and communication blackout and whiteout due to Sun-Earth-Mars geometry. In order to overcome these constraints, the current onboard software was revisited and autonomy features, selectable telemetry rate, event based programming, programmable telemetry and many other complex functionalities were introduced making the onboard software complex. Also, the launch window posed the constraint of schedule and the schedule extension was not acceptable. Carrying out Software Quality Assurance (SQA) of this onboard software required applying a completely different and novel approach which will ensure the robustness of onboard software without schedule overrun. This paper discusses how the new features in onboard software incorporated due to deep space and schedule constraints have impacted the entire Verification & Validation (V&V) activity of onboard software.